JP2739982B2 - Toner for developing electrostatic images - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry toner for developing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing, and the like, and more specifically, to negatively charge a specific metal complex compound. The present invention relates to a toner for developing an electrostatic image, which is contained as an agent (negative polarity control agent).

(Prior art)

Means for developing an electrostatic image formed on an electrophotographic photosensitive member or an electrostatic recording member include a method using a liquid developer (wet development method) and a method using a coloring agent such as a dye or a pigment in a binder resin. Dispersed toner or one-component or two-component dry developer in which this toner is mixed with a solid carrier (dry toner)
(Dry development method) is generally adopted. Each of these methods has advantages and disadvantages, but at present, dry development is often used.

By the way, in a conventional dry toner, a desired chargeability cannot be obtained simply by dispersing a colorant in a binder resin, and therefore, an appropriate amount of a charge control agent is usually added thereto. Typical examples of the conventional charge control agents include (i) those which give a positive charge to the toner, such as a nigrosine oil-soluble dye, a quaternary ammonium salt, an azine dye having an alkyl group, a basic dye, and a basic dye. Dye lakes and the like, and (ii) metal-containing dyes such as chromium-containing monoazo complex, chromium-containing salicylic acid compound complex, and chloro-containing organic dyes (copper phthalocyanine green, chloro-monoazo dye) such as those giving a negative charge to the toner. Can be However, although these charge control agents show good charge controllability in the early stage of use as a toner, their performance gradually decreases over time and the triboelectric chargeability of the toner deteriorates. It is difficult to form a quality image, and the toner image falls off due to friction between the toner or the photosensitive member, collision with a carrier, etc., and adheres to the photosensitive member (so-called toner filming) and becomes contaminated. In particular, this tendency was remarkable under high temperature and high humidity. Moreover, since most of the charge control agents described above are colored substances, they can be used only for toners of the same color tone, and it is difficult to form clear color images especially when used for color toners. there were.

〔Purpose〕

An object of the present invention is to use a colorless (white) or light-colored negative charge control agent that provides stable triboelectricity, so that image quality does not deteriorate even when used for a long time such as continuous copying, and that the photosensitive film is exposed by toner filming. A clear color image can be easily formed without contaminating the body and the like. An object of the present invention is to provide a dry toner for developing an electrostatic image having a long life and excellent environmental stability.

〔Constitution〕

The toner of the present invention is a toner for developing an electrostatic image mainly containing a resin, a colorant and a charge control agent, and has the following general formula I as a negative charge control agent: (However, R ₁ and R ₂ may be the same or different, and include a hydrogen atom, a halogen atom, a C ₁ -C ₈ alkyl group, a C ₁ -C ₈ alkoxy group, a carboxyester group, a nitro group, a sulfonamide group Or a cyano group, and R ₃ is a hydrogen atom or C _1-
Represents an alkyl group of C _8, M is Zn, Cr, Co, Ni, Fe, Cr and A
represents a metal atom selected from l, and m represents the same number as the valence number of M. A metal salt of an indolecarboxylic acid represented by the general formula II: (Wherein R ₁ , R ₂ , M and m are the same as those of the general formula I) and a metal salt of a quinoline carboxylic acid represented by the general formula III: (However, R ₄ and R ₅ may be the same or different, and a hydrogen atom,
C1-C10 alkyl group, amino group or C1-C10
M represents a metal atom selected from Zn, Co, Ni, Fe and Te, and n represents the same number as the valence number of M. Wherein at least one member selected from the group consisting of benzothiazole derivative metal salts represented by the following formula (1) is used.

As described above, the toner of the present invention is characterized in that the negative charge control agent composed of the above-mentioned metal salt is used. These metal complexes can be synthesized by known methods. For example, in the case of a metal salt of the general formula I, an aqueous solution of the corresponding indolecarboxylic acid is prepared by
In the case of the metal salt of the general formula II, the aqueous solution of the corresponding quinoline carboxylic acid is neutralized with an alkali, and an aqueous solution of the salt of the corresponding metal is added to carry out metal exchange. In this case, it can be easily obtained by adding an aqueous solution of a salt of the corresponding metal to an aqueous solution of the corresponding benzothiazole derivative and performing metal exchange. The synthesis example is shown below.

Synthesis Example 1 Indole carboxylic acid 0.1mole dissolved with heating to 70 ° C. in water 50 ml, was neutralized by addition of sodium hydroxide 0.1mole To this is added 0.05mole a ZnSO ₄ · 7H ₂ O. The solution becomes cloudy and a zinc precipitate of indolecarboxylic acid (R ₁ = R ₂ = R ₃ = H, M = Zn in the general formula I) is obtained as a white precipitate.

Synthesis Example 2 Zinc quinoline carboxylate as a white precipitate (R ₁ = R ₂ = H, M = Zn in the general formula II) in the same manner as in Synthesis Example 1 except that quinoline carboxylic acid is used instead of indole carboxylic acid.
Get.

Synthesis Example 3 An aqueous solution of zinc sulfate was added to an aqueous solution of sodium salt of 2-mercaptobenzothiazole to obtain a zinc salt of 2-mercaptobenzothiazole (R ₄ = R ₅ = H, M = Zn in the general formula III).

Specific examples of the metal salts of the general formulas I, II and III obtained as described above are as follows.

Other components used in the toner of the present invention may be exactly the same as the conventional ones. That is, as the binder resin, a homopolymer of styrene such as polystyrene, poly p-chlorostyrene, and polyvinyl toluene and a substituted product thereof; a styrene-p-chlorostyrene copolymer, a styrene-propylene copolymer, and a styrene-vinyl toluene Polymer, styrene-vinyl naphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene
Butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethacrylic acid Methyl copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer Styrene-based copolymers such as polymers, styrene-acrylonitrile-indene copolymers, styrene-maleic acid copolymers, styrene-maleic acid ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate Vinyl, poly Tylene, polypropylene, polyester, polyurethane, polyamide, epoxy resin, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorination Examples include paraffin, paraffin wax, and mixtures thereof.

Polyolefins (low molecular weight polyethylene, low molecular weight polypropylene, polyethylene oxide, polytetrafluoroethylene, etc.), epoxy resins, polyester resins, styrene-butadiene copolymers (monomer ratio of 5 to 5) are particularly suitable as binder resins for pressure fixing. 30: 95-70), olefin copolymer (ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, ethylene-methacrylic acid copolymer, ethylene-methacrylic acid ester copolymer, ethylene-vinyl chloride Copolymer, ethylene-vinyl acetate copolymer, ionomer resin), polyvinylpyrrolidone,
Examples thereof include a methyl vinyl ether-maleic anhydride copolymer, a maleic acid-modified phenol resin, a phenol-modified terpene resin, and a mixture thereof.

Examples of the coloring agent include various dyes and pigments such as carbon black, lamp black, oil black, azo oil black, Sudan black SM, iron black (magnetite), fast yellow C, benzidine yellow, pigment yellow, chrome yellow, quinoline yellow, and Hansa. Yellow G, Nigrosine dye, India First Orange, Irgazine Red, Paranitroaniline Red, Toluidine Red, Dupont Oil Red, Rose Bengal, Carmin FE, Permanent Bordeaux FR
R, Pigment Orange R, Risor Red 2G, Lake Red C, Rhodamine FB, Rhodamine E Lake, Methyl Violet E Lake, Phthalocyanine Blue, Pigment Blue, Ultramarine, Aniline Blue, Calco Oil Blue, Ultramarine Blue, Methylene Blue Chloride,
Phthalocyanine blue, brilliant green E, phthalocyanine green, rhodamine 6G lake, quinacridone, malachite green hexalate, oil yellow
GG, Pomelo First Yellow GGG, Kaya Set Y963,
Kayaset YG, Sumiplast Yellow GG, Pomelo Fast Orange RR, Oil Scarlet, Sumiplast Orange, Orazol Brown E, Pomelo First Scarlet CG, Aizen Spiron Red BEH, Oil Pink OP, Azo pigments (monoazo, disazo and trisazo System), triallylmethane dyes and mixtures thereof.

In the toner of the present invention, in addition to the above components, various plasticizers (dibutyl phthalate, dioctyl phthalate, etc.) for the purpose of improving or adjusting the thermal properties, electrical properties, physical properties, etc. of the toner as necessary, Agents or conductivity-imparting agents (tin oxide, lead oxide, antimony oxide, carbon black, etc.), fluidity improvers or anti-caking agents (colloidal silica, alumina, etc.), abrasives (cerium oxide, alumina, titanium oxide, silicon carbide) ), Lubricants (fluororesin powder, metal salts of higher fatty acids such as zinc stearate, etc.), and fixing aids (such as low molecular weight polyolefins). Also, to adjust the charging characteristics,
If the amount is small, a known charge control agent can be added.

It is particularly effective to use the dry toner of the present invention as a two-component developer by mixing it with a carrier. (Referred to as magnetic toner).

As the carrier used for the two-component type developer, all known carriers can be used. For example, a) iron oxide such as magnetite, hematite, ferrite, or an iron oxide-based alloy; b)
Ferromagnetic metals such as iron, cobalt and nickel; c) ferromagnetic metals and aluminum, copper, lead, magnesium, tin, zinc,
Powders of magnetic materials such as alloys with nonmagnetic metals such as antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium and mixtures thereof; glass beads; and styrene-acrylate on their surfaces Copolymer, silicone resin,
Those coated with a resin such as a polyamide resin or an ionomer resin are exemplified. The particle size of these carriers is about
About 40 to about 200 μm (400 to 70 mesh) is appropriate.

The magnetic material used for the magnetic toner may be the same as that used for the two-component developer. In the case of a magnetic toner, the average particle size of the magnetic powder is suitably about 0.1 to 2 μm.

The toner of the present invention is produced by kneading and melting the above components by a roll mill or the like, cooling, and then pulverizing and classifying the resulting mass as in the conventional case. In the case of a two-component toner, the amount of the colorant and the amount of the negative charge control agent to be used are suitably about 1 to 30 parts by weight and about 0.1 to 30 parts by weight, respectively, per 100 parts by weight of the resin component. In this case, if the amount of the negative charge control agent is less than 0.1 part by weight, the negative charge of the toner is insufficient and is not practical, and if it exceeds 30 parts by weight, the charge amount of the toner is too large and electrostatic attraction with the carrier is caused. Due to the increase in force, there arises a problem that the fluidity of the developer decreases and the image density decreases. Also in the case of a one-component toner, the amount of the resin, the colorant and the negative charge control agent used is 2
The amount of the magnetic material is usually about 20 to 200 parts by weight per 100 parts by weight of the resin component, preferably 40 to 40 parts by weight.
~ 150 parts by weight.

Hereinafter, the present invention will be described with reference to examples. All parts are parts by weight.

Example 1 100 parts of a styrene-n-butyl methacrylate copolymer 100 parts of polypropylene 5 parts of CI Pigment Blue 15 5 parts of a metal salt of No. I- (1) 5 parts After sufficiently stirring and mixing in a Henschel mixer, a roll mill was used. At 130 to 140 ° C. for about 30 minutes, and cooled to room temperature. The kneaded product was pulverized and classified to obtain a blue toner having a particle size of 5 to 15 μm.

100 to 250 parts coated with 3 parts of this toner and silicone resin
97 parts of a mesh ferrite carrier were mixed by a ball mill to prepare a two-component type developer.

Use this developer as an electrophotographic copier (FT-4060 manufactured by Ricoh Company)
, And a clear blue image was obtained when copying was performed. The image quality did not change even after continuous copying of 200,000 sheets.

When the charge amount of this toner was examined by a blow-off method,
The initial charge amount was −22.5 μc / g, and the charge amount of the toner after copying 200,000 sheets was −21.5 μc / g, and almost no difference from the initial value was recognized. Also, under a high humidity environment of 35 ° C. and 90% RH and a low humidity environment of 15 ° C. and 10% RH, almost the same images as in the case of normal humidity were obtained. No filming of the toner on the photoreceptor was observed.

Example 2 Styrene to 2-ethylhexyl acrylate copolymer 100 parts Polyethylene 5 parts CI Pigment Red 81 5 parts CI Pigment Red 48 3 parts A mixture consisting of No. I- (2) metal salt 5 parts was prepared in the same manner as in Example 1. After melt-kneading, the mixture was pulverized and classified to obtain a red toner having a particle size of 5 to 20 μm. Next, 3 parts of silicon carbide (particle size: about 2 μm) was added to 100 parts of the toner.
A one-component developer was prepared by sufficiently stirring and mixing with a speed kneader.

When this developer was put into a developing device as shown in FIG. 1 and copying was performed, a clear red image was obtained. This image quality did not change after continuous copying of 50,000 sheets.

In addition, the charge amount (specific charge amount Q /
M) was measured with a suction-type specific charge measuring device (a device for measuring the Q / M by sucking and trapping the toner on the member in a Faraday cage having a filter layer on the exit side), and found to be -9.3. It was confirmed to have a sufficient charge amount of μc / g. The charge after 50,000 copies is -8.5 μc / g
So, there was almost no difference from the beginning. Further, an image almost equivalent to that under normal humidity was obtained under both high and low humidity. No toner filming on the photoreceptor was observed.

Incidentally, the developing method shown in FIG. 1 will be described.
The toner 6 stored in the toner tank 7 is
And the toner 6 is forcibly brought to the sponge roller 4 by the
Is supplied to the sponge roller 4. The toner 6 taken in by the sponge roller 4 is carried to the toner conveying member 2 by the rotation of the sponge roller 4 in the direction of the arrow, and is rubbed and electrostatically or physically attracted. It rotates strongly in the direction of the arrow, and a uniform thin toner layer is formed by the elastic blade 3 and is triboelectrically charged. Thereafter, the toner image is transported to the surface of the electrostatic image carrier 1 which is in contact with or in proximity to the toner conveying member 2, and the electrostatic image is developed. In this embodiment, a Se photoconductor is used as an electrostatic image carrier, and after DC charging of +800 V is applied thereto, an image is exposed to form an electrostatic image, and then the electrostatic image is developed.

Example 3 Epoxy resin 100 parts Polypropylene 5 parts CI Pigment Blue 15 2 parts CI Pigment Yellow 17 5 parts No.I- (5) metal salt 3 parts A mixture composed of 3 parts was melt-kneaded in the same manner as in Example 1 and then crushed and classified. As a result, a green toner having a particle size of 5 to 20 μm was obtained.

Next, 5 parts of the toner and 100 parts of 100 to 200 mesh iron powder were mixed by a ball mill to prepare a two-component developer.

Thereafter, copying was performed in the same manner as in Example 1 using this developer. As a result, a clear green image was obtained. This image remained unchanged even after continuous copying of 200,000 sheets. The image was almost the same as the image below. The charge amount of the toner was -20.2 μc / g at the initial stage and -19.3 μc / g after 200,000 sheets were copied, and there was almost no difference. No filming of the toner on the photoreceptor was observed.

Example 4 100 parts of an unsaturated polyester resin 10 parts of carbon black 1 part of a metal-containing monoazo dye 1 part A mixture of 5 parts of a metal salt of No. I- (6) was melt-kneaded in the same manner as in Example 1 and then pulverized and classified. A black toner having a particle size of about 20 μm was obtained.

Next, 2 parts of silicon carbide (particle size: 2 μm) and 0.1 part of hydrophobic colloidal silica were added to 100 parts of the toner, and stirred and mixed in the same manner as in Example 2 to prepare a one-component developer.

Thereafter, when this developer was placed in the same developing apparatus as in Example 2 and copying was carried out in the same manner, a clear black image was obtained. This image remained unchanged even after continuous copying of 50,000 sheets, and was kept in a low humidity even under high humidity. The image was almost the same even under normal humidity. The charge amount of toner (measured by a specific charge measuring device using a suction method) is -8.3 μc / g at the initial stage and -7.1 μc / g after 50,000 copies.
It was almost the same. No filming of the toner on the photoreceptor was observed.

Examples 5 to 8 Two-component dry developers were prepared in the same manner as in Example 1 using the developer compositions shown in Table 1. Table 1 also shows the image properties and chargeability of these toners. It should be noted that the toners in all of the examples obtained the same image quality under high humidity or low humidity as under normal humidity. Also, no toner filming on the photoreceptor was observed in any of the examples.

Example 9 5 to 20 μm in the same manner as in Example 1 except that 4 parts of the metal salt of No. I- (21) was used instead of 5 parts of the metal salt of No. I- (1).
Was obtained.

Next, 2.5 parts of this toner and 97.5 parts of a 100 to 250 mesh ferrite carrier were mixed to prepare a two-component developer.

Thereafter, copying was performed in the same manner as in Example 1 using this developer. As a result, a clear blue image was obtained, and the image quality remained unchanged even after continuous copying of 200,000 sheets.

The initial charge amount of this toner is −20.5 μc / g,
The toner charge after copying 10,000 sheets is -19.2 μc / g
Almost no difference from the initial value was observed. In addition, almost the same image was obtained under high humidity and low humidity as under normal humidity. No filming of the toner on the photoreceptor was observed.

Example 10 Styrene to 2-ethylhexyl acrylate copolymer 10
0 part Polypropylene 5 parts CI Pigment Red 57 5 parts CI Pigment Red 48 3 parts No.I- (22) 3 parts of a metal salt mixture is melt-kneaded in the same manner as in Example 1 and then pulverized and classified to 5 to 20 μm. A red toner having a particle size of was obtained. Next, 3 parts of silicon carbide (particle size: about 2 μm) and 0.1 part of hydrophobic colloidal silica were added to 100 parts of the toner, and the mixture was sufficiently stirred and mixed with a speed kneader to prepare a one-component developer.

A developing device as shown in FIG. 1 (however, in this embodiment, an organic photoreceptor is used as an electrostatic latent image holding member)
And a clear red image was obtained. This image quality did not change after continuous copying of 50,000 sheets. In the present embodiment, the organic photoreceptor is charged with -800 V DC, and then image-exposed to form an electrostatic image. Subsequently, the electrostatic image is reversely developed.

Further, the charge amount of the toner on the toner conveying member was determined according to the second embodiment.
When measured with the same suction method specific charge amount measuring device as
It was confirmed to have a sufficient charge amount of 2.1 μc / g. The charge amount after copying 50,000 sheets was -9.5 μc / g, and there was almost no difference from the initial charge. Further, an image almost equivalent to that under normal humidity was obtained under both high and low humidity. No filming of the toner on the photoreceptor was observed.

Example 11 The procedure of Example 3 was repeated except that 4 parts of the metal salt of No. I- (23) was used instead of 3 parts of the metal salt of No. I- (5), and that polypropylene was changed to polyethylene. A green toner having a particle size of about 20 μm was obtained.

Next, 3.5 parts of the toner and 96.5 parts of a 100 to 200 mesh ferrite carrier were mixed to prepare a two-component developer.

Thereafter, copying was performed in the same manner as in Example 1 using this developer. As a result, a clear green image was obtained, and the image quality did not change even after continuous copying of 200,000 sheets.

The initial charge amount of this toner is -18.5 μc / g,
The charge amount of the toner after 10,000 copies is -16.9 μc / g
Almost no difference from the initial value was observed. In addition, almost the same image was obtained under high humidity and low humidity as under normal humidity. No filming of the toner on the photoreceptor was observed.

Example 12 Unsaturated polyester resin 100 parts Polypropylene 5 parts Carbon black 10 parts No.I- (25) 2 parts of a metal salt was melt-kneaded in the same manner as in Example 1 and then pulverized and classified to 5 to 25 μm. A black toner having a particle size was obtained.

Next, 2 parts of silicon carbide (particle size: 2 μm) and 0.1 part of hydrophobic colloidal silica were added to 100 parts of the toner, and stirred and mixed in the same manner as in Example 2 to prepare a one-component developer.

Thereafter, when this developer was placed in the same developing apparatus as in Example 2 and copying was carried out in the same manner, a clear black image was obtained. This image remained unchanged even after continuous copying of 50,000 sheets, and was kept in a low humidity even under high humidity. The image was almost the same even under normal humidity. The charge amount of the toner (measured by a specific charge measuring device using a suction method) is -24.6 µc / g at the initial stage and -23.1 µc after 50,000 copies.
/ g hardly changed. No filming of the toner on the photoreceptor was observed.

Examples 13 to 17 Two-component dry developers were prepared in the same manner as in Example 1 using the developer compositions shown in Table-2. Table 2 also shows the image properties and chargeability of these toners. It should be noted that the toners in all of the examples obtained the same image quality under high humidity and low humidity as under normal humidity. Also, no toner filming on the photoreceptor was observed in any of the examples.

Example 18 A blue toner having a particle size of 5 to 15 μm was obtained in the same manner as in Example 1 except that the metal salt used was No. II- (1).

Next, 3 parts of this toner and 97 parts of a 100 to 250 mesh ferrite carrier coated with polymethyl methacrylate were mixed to prepare a two-component developer.

Thereafter, copying was performed in the same manner as in Example 1 using this developer. As a result, a clear blue image was obtained, and the image quality did not change even after continuous copying of 200,000 sheets.

The initial charge amount of this toner is −20.5 μc / g,
The toner charge after copying 10,000 sheets is -19.8 μc / g
Almost no difference from the initial value was observed. In addition, almost the same image was obtained under high humidity and low humidity as under normal humidity. No filming of the toner on the photoreceptor was observed.

Example 19 The same procedure as in Example 2 was repeated except that 5 parts of the metal salt of No. I- (2) was replaced by 3 parts of the metal salt of No. II- (3).
Thus, a red toner having a particle size of m was obtained.

Thereafter, a one-component developer was prepared using this toner in the same manner as in Example 2, and copying was performed in the same manner as in Example 2. As a result, a clear red image was obtained, and the image quality was 50,000. It did not change after continuous copying. The charge amount of this toner was -8.5 µc / g at the initial stage and -7.6 µc / g after 50,000 copies, and there was almost no difference. Further, an image almost equivalent to that under normal humidity was obtained under both high and low humidity. No filming of the toner on the photoreceptor was observed.

Example 20 5-20 μm in the same manner as in Example 3 except that 2 parts of the metal salt of No. II- (6) was used instead of 3 parts of the metal salt of No. I- (5).
Thus, a green toner having a particle size of m was obtained.

Thereafter, a two-component developer was prepared using this toner in the same manner as in Example 3, and copying was performed in the same manner as in Example 1. As a result, a clear green image was obtained. The image remained almost the same under both high and low humidity conditions. The charge amount of the toner was -17.8 µc / g at the initial stage and -17.3 µc / g after 200,000 sheets were copied, which was almost unchanged. No filming of the toner on the photoreceptor was observed.

Example 21 A black toner having a particle size of 5 to 20 μm was obtained in the same manner as in Example 4 except that the metal salt used was No. II- (5) and the amount of the metal-containing monoazo dye was 2 parts. Was.

Thereafter, a one-component developer was prepared using this toner in the same manner as in Example 4, and copying was performed in the same manner as in Example 2. As a result, a clear black image was obtained, and the image quality was 50,000. It did not change after continuous copying. The initial charge amount of the toner is -12.1μc / g and -10.9μc after 50,000 copies.
There was almost no difference at / g. In both high and low humidity, almost the same image was obtained as in normal humidity. No filming of the toner on the photoreceptor was observed.

Examples 22 to 25 Toners were prepared in the same manner as in Example 1 using the developer compositions shown in Table 3, and the image properties and chargeability of these toners were also shown in the same table. In each of the examples, almost the same image was obtained under high or low humidity as under normal humidity. Also, no filming of the toner on the photoreceptor was observed.

Example 26 5 to 15 μm in the same manner as in Example 1 except that 3 parts of the metal salt of No. III- (1) was used instead of 5 parts of the metal salt of No. I- (1).
A blue toner having a particle size of m was prepared.

Next, 2.5 parts of this toner and 97.5 parts of the silicone resin-coated carrier used in Example 1 were mixed with a ball mill to prepare a two-component developer.

Thereafter, copying was performed in the same manner as in Example 1 using this developer. As a result, a clear blue image was obtained, and the image quality did not change even after continuous copying of 200,000 sheets. The initial charge of the toner is -16.2μc / g, and after copying 200,000 sheets, -15.1μc / g
And there was almost no difference. In addition, almost the same image was obtained under high humidity and low humidity as under normal humidity. No toner filming on the photoreceptor was observed.

Example 27 Styrene to 2-ethylhexyl acrylate copolymer 10
0 parts Polypropylene 5 parts CI Pigment Red 57 5 parts CI Pigment Red 48 3 parts No.III- (2) 5 parts of a metal salt mixture is melt-kneaded in the same manner as in Example 1 and then pulverized and classified to 5 to 20 μm. A red toner having a particle size of was obtained.

Next, 100 parts of this toner was mixed with silicon carbide (particle size: about 2 μm) 3
And 0.1 part of hydrophobic colloidal silica were added, and the mixture was sufficiently stirred and mixed with a speed kneader to obtain a one-component developer.

Hereinafter, this developer is put into the developing device used in Example 2,
Upon copying, a clear red image was obtained.
This image quality did not change after continuous copying of 50,000 sheets. The charge amount of this toner was measured by a suction-specific-charge-amount measuring apparatus.
There was almost no difference from c / g. In addition, almost the same image was obtained under high humidity and low humidity as under normal humidity. No toner filming on the photoreceptor was observed.

Example 28 Epoxy resin 100 parts Polyethylene 5 parts CI Pigment Blue 15 5 parts CI Pigment Yellow 175 5 parts No.III- (5) 4 parts of a metal salt A mixture of 4 parts was melt-kneaded in the same manner as in Example 1 and then crushed and classified. As a result, a green toner having a particle size of 5 to 20 μm was obtained.

Next, 3.5 parts of this toner and 96.5 parts of a 100 to 200 mesh iron powder carrier were mixed by a ball mill to prepare a two-component developer.

Thereafter, copying was performed in the same manner as in Example 1 using this developer. As a result, a clear green image was obtained, and this image did not change even after copying 200,000 sheets. The charge amount of the toner was −17.8 μc / g at the initial stage and −16.2 μc / g after copying 200,000 sheets, and there was almost no difference. In addition, almost the same image was obtained under high humidity and low humidity as under normal humidity. No filming of the toner on the photoreceptor was observed.

Example 29 100 parts of unsaturated polyester 5 parts of polypropylene 10 parts of carbon black A mixture of 2.5 parts of a metal salt of No. III- (6) was melt-kneaded in the same manner as in Example 1 and then pulverized and classified to obtain particles having a particle size of 5 to 25 μm. A black toner having a diameter was obtained.

Next, 2.5 parts of silicon carbide (particle diameter: 2 μm) and 0.1 of hydrophobic colloidal silica were added to 100 parts of the toner, and sufficiently mixed by stirring with a speed kneader to obtain a one-component developer.

Thereafter, this developer was placed in the developer used in Example 2 and copying was performed. As a result, a clear black image was obtained. This image quality did not change after continuous copying of 50,000 sheets. The charge amount of this toner was measured by a specific charge amount measuring device using a suction method. The initial charge was −9.5 μc / g, and after copying 50,000 sheets, −8.8 μc / g.
And there was almost no difference. Further, an image almost equivalent to that under normal humidity was obtained under both high and low humidity. No filming of the toner on the photoreceptor was observed.

Examples 30 to 33 Two-component dry developers were prepared in the same manner as in Example 1 using the developer compositions shown in Table-3. Table 4 also summarizes the image properties and chargeability of these toners. It should be noted that the toners in all of the examples exhibited image quality equivalent to that under normal humidity even under high and low humidity. Also, no toner filming on the photoreceptor was observed in any of the examples.

[Effect] The toner of the present invention contains the above-mentioned metal salts as a negative charge control agent, and therefore has the following advantages.

1) Stable triboelectricity of negative polarity is obtained.

2) Even when used for a long time, a high-quality clear image (especially a color image) equivalent to the initial one can be obtained, and therefore, the life is long.

3) There is no contamination of carriers and the like due to dropping of the charge control agent.

[Brief description of the drawings]

FIG. 1 is a schematic view of an example of a developing device used in an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Electrostatic latent image carrier, 2 ... Toner conveying member 3 ... Elastic blade, 4 ... Sponge roller 5 ... Stirring blade, 6 ... Toner 7 ... Toner tank

Claims (2)

(57) [Claims] 1. An electrostatic image developing toner comprising a binder resin, a colorant and a charge control agent as main components, wherein a general formula I: (However, R ₁ and R ₂ may be the same or different, and include a hydrogen atom, a halogen atom, a C ₁ -C ₈ alkyl group, a C ₁ -C ₈ alkoxy group, a carboxyester group, a hydroxy group, a nitro group, R ₃ represents a hydrogen atom or a C _{1 to} C ₈ alkyl group, and M represents Zn, Co, N
represents a metal atom selected from i, Fe, Cr and Al;
Represents the same number as the valence number of M. A) a metal salt of an indolecarboxylic acid represented by the general formula II: (Wherein R ₁ , R ₂ , M, and m are the same as those of the general formula I).
A toner for developing electrostatic images, characterized by using seeds. 2. An electrostatic image developing toner comprising a binder resin, a colorant and a charge control agent as main components, wherein the negative charge control agent has the general formula III: (However, R ₄ and R ₅ may be the same or different and represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an amino group or an alkylamino group having 1 to 10 carbon atoms, and M is Zn, Co, Ni, Wherein n represents a metal atom selected from Fe and Te, and n represents the same number as the valence number of M.) A benzothiazole derivative metal salt represented by the following formula: